在恒流膜电容离离子 (MCDI):问题和解决方案中的离子不充分脱离
Zhizhao He1, Yingnan Li1, Yuan Wang1
1UNSW Centre for Transformational Environmental Technologies, Yixing, Jiangsu Province 214206, P. R. China; School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
Water research
|July 2, 2023
概括
膜电容脱离离子 (MCDI) 性能随着二价离子积聚而增加的水硬度而下降. 将排放到负潜力显著提高了海水淡化效率和水回收.
科学领域:
- 环境科学 环境科学
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
背景情况:
- 膜电容脱离离子 (MCDI) 是一个有前途的淡水技术.
- 以前的MCDI研究主要使用像NaCl这样的单电解质溶液.
- 有限的研究存在于MCDI性能与多电解质溶液,特别是关于水的硬度.
研究的目的:
- 为了评估MCDI的海水淡化性能,使用具有不同硬度水平的料溶液.
- 确定硬水性能下降的主要原因.
- 探索改善MCDI效率和运营稳定的策略.
主要方法:
- 使用不同硬度度的料溶液进行了MCDI海水淡化实验.
- 测量了性能指标,包括海水淡化时间,移除的电荷,水回收和生产率.
- 分析包括检查在恒流和负电位放电期间的电压配置和废水离子度.
主要成果:
- 增加的水硬度显著降低了MCDI性能,减少了海水淡化时间,去除电荷,回收水和生产力.
- 在恒定电流下放到0V时,二价离子的不充分脱离被确定为主要原因.
- 将排水量降至负潜力 (例如, -0.3 V) 显著改善了海水淡化时间,消除了电荷,恢复了水,提高了生产率.
结论:
- 水的硬度对MCDI的性能有负面影响,主要是由于双价离子脱吸中的挑战.
- 将MCDI细胞排放到负潜力是一个可行的策略,以提高再生和整体淡化效率.
- 这种方法具有大规模MCDI应用的潜力,可以提高性能并减少维护需求.
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